Man that is great! I never noticed that before and now I can get a better handle on my efficiency. I would however still like to see a feature that allowed us to plug in our actual pre-boil gravity so that we can get accurate mash efficiency verses total brew house efficiency.

If you have BTP set so that the pre-boil gravity and volume are correct, then the Efficiency value is your Mash Efficiency.

If you want to have the program calculate that number from a number you type in, there's an easy way to get that:
• with the Lock/scale button not checked, temporarily set the Final Volume to your pre-boil volume,
• open the Analysis tab, and type your pre-boil gravity in as your OG.
BTP will then calculate and display your Mash Efficiency in the Efficiency window.

To return your original setting: With the Lock box still not checked, re-type that volume into the Kettle Volume box, and everything will be reset, your Mash Efficiency will still be correct, and BTP will display your proper OG in the Analysis tab, if your evaporation rates are correct.